In a normal female body, the levator ani muscles close the pelvic floor and support the vagina. This results in little force being applied to the fascia and ligaments that support the vagina. Increases in abdominal pressure, failure of the muscles to keep the pelvic floor closed, and damage to ligaments and fascia can all contribute to the development of prolapse. Vaginal prolapse changes the position of the vagina, which can lead to discomfort, urinary incontinence, and incomplete emptying of the bladder. In severe cases, vaginal prolapse conditions can even cause the vagina to become positioned outside of the body. One specific type of prolapse is referred to as posterior vaginal prolapse, which may additionally cause defecatory problems such as tenesmus and difficulty in stool evacuation. Conditions of posterior vaginal wall prolapse can involve descent of the rectum into the vagina, often termed a rectocele, or the presence of small intestine in a hernia sac between the rectum and vagina, called an enterocele.
Broadly, there are four types based on suspected etiology. Congenital enteroceles are thought to occur because of failure of fusion or reopening of fused peritoneal leaves down to the perineal body. Post-hysterectomy vault prolapse can result from a lack of support from detachment of the uterosacral ligaments from the uterus at the time of hysterectomy. Enterocele may occur because of failure to reapproximate the superior aspects of the pubocervical fascia and the rectovaginal fascia at the time of a surgery. Iatrogenic prolapse may occur after a surgical procedure that changes the vaginal axis, such as certain surgical procedures for treatment of incontinence. With regard to rectoceles, the most common type of rectocele results from disruption of connective tissue supports of the rectovaginal fascia from its normal attachments to the uterosacral ligaments. Posterior or post-hysterectomy enteroceles may accompany rectoceles.
Several factors have been implicated as being involved in causing vaginal prolapse. It is thought that individual women have differing inherent strength of the relevant connective tissue. Further, loss of connective tissue strength might be associated with damage at childbirth, deterioration with age, poor collagen repair mechanisms, and poor nutrition. Loss of muscle strength might be associated with neuromuscular damage during childbirth, neural damage from chronic straining, and metabolic diseases that affect muscle function. Other factors involved in prolapse include increased loads on the supportive system as seen in prolonged lifting or chronic coughing from chronic pulmonary disease, or some disturbance in the balance of the structural support of the genital organs. Obesity, constipation, and a history of hysterectomy have also been implicated as possible factors. In particular, the vaginal angle may be altered upon removal of the uterus in a hysterectomy, causing increased pressure at a more acute angle and thereby accelerating the prolapse.
Various techniques have been used to attempt to correct or ameliorate prolapse and prolapse symptoms, with varying degrees of success. Nonsurgical treatment of prolapse involves measures to improve the factors associated with prolapse, including treating chronic cough, obesity, and constipation. Vaginal pessaries are the primary type of nonsurgical treatment, but potential complications can occur such as vaginal wall ulceration. Other nonsurgical treatments may include pelvic muscle exercises or supplementation with estrogen. These therapies may alleviate some symptoms and temporarily provide some relief to the patient, but any actual hernia will remain.
Surgical treatments of posterior prolapse can involve vaginal and abdominal procedures to reapproximate the attenuated tissue using sutures or a biological or synthetic implant to provide continuing support of the reapproximated tissue following the procedure. Implants that have been used to address pelvic organ prolapse are described, for example, in U.S. Patent Publication No. 2004/0039453, entitled “Pelvic Health Implants and Methods”, and U.S. Patent Publication No. 2005/0245787, entitled “Method and Apparatus for Treating Pelvic Organ Prolapse”, which patent applications are incorporated entirely herein by reference.
An example of a specific implant product designed for treating conditions of vaginal vault prolapse is a product commercially available from American Medical Systems, Inc., of Minnetonka, Minn. under the trade designation “APOGEE”. Very generally, devices of this type are designed to be implanted in a manner to support vaginal tissue. These devices and similar products can include various designs, such as “strips” of a single material or pieces of the same or different materials connected together (e.g., mesh, tape, optionally including synthetic or biological tissue portions) to form an implant that can be attached at one portion to vaginal tissue, with another portion attached at a position of the anatomy that supports the vaginal tissue.
Another pelvic floor disorder that can occur in patients is referred to as urinary incontinence or involuntary loss of urinary control, which is a problem that afflicts men, women, and children of all ages. A variety of treatment options for incontinence are currently available. Some of these include external devices, behavioral therapy (such as biofeedback, electrical stimulation, or Kegel exercises), and prosthetic devices. Depending on the age, medical condition, and personal preference of a patient, surgical procedures can additionally or alternatively be used to completely restore continence.
One type of surgical procedure found to be an especially successful treatment option for incontinence in both men and women is a referred to as a sling procedure. Sling procedures typically entail surgically implanting a biocompatible implant or “sling” to support the bladder neck or urethra in manners that are somewhat similar to those described above for prolapse correction techniques. Sling procedures are discussed in U.S. Pat. Nos. 5,112,344; 5,611,515; 5,842,478; 5,860,425; 5,899,909; 6,039,686; 6,042,534; 6,110,101; 6,478,727; 6,638,211; and PCT Publication Nos. WO 02/39890 and WO 02/069781, for example.
Some “pubomedial” sling procedures involve an abdominal incision and installation of a sling between the rectus fascia in the abdominal region to a position below the urethra, and back again to the rectus fascia. A conventional procedure in females is to surgically place a sling by entering the abdominal cavity through an incision in the patient's pubovaginal region. In males, one exemplary conventional method involves surgical placement of a sling by entering the abdominal cavity through an abdominal incision.
Other methods for treating pelvic conditions involve installation of a sling below the urethra through incisions made at the inner thigh (e.g., in the perineal skin facing the obturator and in the groin), and using a tissue path extending through the obturator. These procedures can be referred to as “transobturator” methods, which are described, for example, in U.S. Pat. No. 6,911,003 and U.S. Patent Publication Nos. 2003/0171644 and 2005/0143618, the entireties of each being incorporated herein by reference.
While these described devices and methods of treating urinary incontinence and vaginal prolapse can be effective, safe, and long-lasting, there is ongoing effort toward improving these devices and methods.